Combustion gas and steam turbine arrangement



A; G. FORSYTH COHBUSTION yf-AS AND STEAM TURBINE ARRANGEMENT Filed D'ec.13. 1944 2 Sheets-Sheet 2 I1 QN km' wm A\ /v I \A.| A| Al* Y l'. o I u H5i e mnmf, *uw n WN ll.' v x All, Al 4l @W :mv 5N NW e k mw 4| I/J/...Nn Q' J Al 0| 1| All! 4/ K1 NW .x/r WW f ma I f v WQ 5W f lg PataatadAaa. 24, 194s COMBUSTION GAS AND STEAM TUBBINE ARRANGEMENT ArchibaldGraham Fai-mh, Chaam, England, Hassigner' to The Fairey AviationCompanyLimited, Hayes, Middlesex, England Apauaauan December 13, 1944,serial No. neuss 1 Claim.

This invention relates to turbines of the type used as prime movers inself propelled vehicles, and more particularly for use in aircraft. Theinvention has particular reference to turbines driven by products ofcombustion and to means for rendering such turbines more elli-cient.More explicitly, the invention includes a water cooling Jacket for theturbine so arranged that the cooling water in its path of travel ishighly heated and converted into steam and means are provided tosuperheat such steam and cause it to impinge uponl the turbine blades toassist in driving and.

turbine after such gases have passed through the turbine and forcondensing water from the steam formed in the water jacket after thesteam has performed its work on the turbine blades, such extracted andcondensed water being added to the water supply for the cooling system.

Still another object of the invention resides in edecting such objectsin a compressor-turbine system in which the compressor and turbine aremounted coaxially and with the turbine surrounding the compressor.

These and other objects of the invention will become more apparent fromthe following description and iclaim when read in conjunction with theaccompanying drawings in which:

Figure 1 is a longitudinal sectional view through a compressor-turbinearrangement in which the invention has Ibeen incorporated, portions ofthe device being shown in elevation for purposes of simplification, and

Figure 2 is a diagrammatic view of the invention, showing the circuitpaths of the exhaust gases, steam and water.

While the invention, as will be later appreciated, can be applied tovarious types of turbines, it has here been illustrated and will bedescribed as applied to a compressor-turbine arrangement in which thecompressor and tur-bine are coaxially mounted with the turbinesurrounding the compressor and in which the turbine is connected todrive the propeller of an aircraft.

(Cl. 6H?) III In my copending applications, Serial No. 544,788, illedJuly 13, 1944. (now Patent No. 2,423,183, issued July` 1, 1947,) andSerial No. 515,013, iiled December 20, 1943, the latter now abandoned,Jet propulsion units employing coaxially mounted compressors andturbines have been shown. In such applications the products ofcombustion emerging from the turbine are elnployed for jet propulsion.In accordance with the example of the present invention as illustrated',the emerging gases are not used for iet propulsion purposes. but arepassed through a condenser which condenses water present in the productsof combustion. The turbine is here employed solely for driving apropeller.

So that the invention will be better understood it is believed expedientto describe first the compressor-turbine arrangement illustrated. The

application of the invention to such a systemV can then be made clear.

The power unit includes a center longitudinal hollow shaft Il mountedfor rotation about its longitudinal axis. The shaft I0 is supported forrotation by the bearings II and I2. Secured to the shaft I0 to rotatetherewith .are a series of evenly spaced compressor bladesA I3 lwhichextend radially outwards from the shaft tov a cylindrical tubular memberIl which is fixed to a rotata'ble sleeve 5I! by spider 8 or, if desired,is formed integral with-the sleeve.

Disposed concentr'ically with respect to the cylindrical tubular memberI4 and the shaft I0 is the outer part of the casing I6, which outer partis frusta-conical inform with its larger diameter toward the rear end ofthe unit (the right end in x Figure `1) The inner surface of thecylindrical tubular f member I4 is provided with evenly spaced comapressor blades I5. These aredisposed alternately with the blades I3 onthe shaft I0.

The outer surface of the cylindrical tubular member I4 is provided withevenly spaced tur-' bine blades I1, rigidly secured thereto. These lblades I1 extend radially outward toward the into the rear end of thecompressor, as indicatedby the arrow. A butterfly valve 20 or the like,

actuated by the pilot is adapted to control the amount of air enteringthe compressor. Air compressed by the compressor is expelled toward thefront into a number of combustion chambers 2| which have smoothly curvedwalls. Fuel Jets 22 are adapted to inject a fuel mixture into thecombustion chambers, thuseffecting combustion.

The space between the outer wall of the cylindrical tubular member I4and the casing I6 and the blades I1, I8, disposed therein, comprise aturbine. Products of combustion from the combustion chambers 2| aredirected through this turbine toward the rear and finally enters outletpassages 23.

The propeller hub and-shaft arrangement is disposed forwardly of theturbine and the prol peller is connected to be driven by the turbinethrough an epicyclic gear train. Disposed on the hollow shaft 21 forfree retention thereon is the propeller hub 30. Bearings 3I and 32 areprovided for this purpose. The propeller hub 30 supports a plurality ofpropeller blades, such as 33, the pitch of which may be varied bypitchchanging means 34 driven by a small electric motor 35 or the like.The details of the pitchchanging mechanism form no part of the instantinvention and therefore need not be described.

Secured within the hollow shaft 21 is a cylinder 36 provided with apiston 31 connecting with a rod 38 which extends through the front wallof the cylinder 36 and forwardly to the front end of the hollow shaft21. The rod 38 is secured to the member 39 which is in the form of a capsplired to the hollow shaft 21. This cap 39 is provided with an annularflange 4I formed with gear teeth 42 adapted to engage teeth on a ringmember 43 rigid with the propeller hub 30.

The cylinder 36 in the hollow shaft 21 is connected by passageways` witha hydraulic system generally indicated by the reference numeral 44 andadapted to supply iiuid under pressure to the cylinder 36 on either sideof the piston 31 to move it selectively, either to the right or to theleft. When the left piston 31 is moved to the left the cap member 39will also be moved to the left so that the teeth 42 on its flange 4Iwill disengage theteeth on the ring member 43. The propeller hub 30 willthen be free from any rotary movement imparted to the hollow shaft 21.When, however, the piston 31 is moved to the right, the teeth willlengage and the propeller hub 30 must partake in any rotation impartedto the hollow shaft 21.

The inner encl of the hollow shaft 21 is provided with an outwardlyextending flange 45 terminating in an annular ring gear 46 having ytubular member I4 or may be integral therewith.

It will be noted that the mechanism described includes the epicyclicgear system, which, when .the cylindrical tubular member I 4,is rotated,im-

parts rotation to the hollow shaft 21, thus driving the propeller. VInaccordance with the present invention, however, the drive between thecylindrical tubular member lI4 and the propeller hub may be direct anddevoid of the clutching and declutching arrangement described.

At the rear end of the unit there is a shaft 52 splined to the shaft I0at its forward end. This shaft 52 extends rearwardly to a clutchingarrangement generally indicated by the reference numeral 53. Surroundingthe shaft 52 is a sleeve 54, the forward end of which is rigid androtates with the cylindrical tubular member I4. The rear end of thesleeve 54 extends into the clutch mechanism 53.

The clutching mechanism to which reference has been made Imay be of anydesired form and, for example, may be similar to that disclosed in mysaid copending application Serial No. 544,788, iiled July 13, 1944. Thepurpose of the clutching mechanism is to render it possible to providetwo degrees of compression. When the .clutching mechanism is in clutchedposition the cylindrical tubular member I4 upon rotating will, throughthe clutching mechanism 53, cause the shaft Ill and its compressorblades I3 to rotate in the direction contra to the blades I5 of thecylindrical tubular member I4. If, however, the clutch mechanism is indeclutched position, the shaft I0 and its blades I3 will remainstationary and only the cylindrical tubular member I4 and its blades I5will rotate and a lesser degree of compression will consequently beeffected.

The present invention as applied to such a system will now be described.

Directly to the rear of the propeller 33 is an annular water tank 55which comprises the reservoir for the cooling water. The water is drawnfrom the tank 55 at the bottom by the pump 56 and is forced by the pumpthrough the pipe 51 (in the direction of the arrows in Figure 2) to therear of the water cooling jacket 58 in the casing I6.

The cooling jacket 58 is provided with a passage 53 which is spiral inform so that the water travels in a spiral path from the rear to thefront. During such travel it is heated by the heat from the turbine andby the time it reaches the end of the passage indicated by 6I)` it hasbeen converted into steam.

It should be mentioned at this-point that the pump 56 is a metering pumpwhich can be adjusted so that it will pump into the cooling jacket 58only such amounts of water as the heat from the turbine is capable ofconverting into steam during the time of travel of the water through 4verted emerges under pressure at the end 60 of y chamber 62', the uppersurface 63 of which is teeth 41 in its inner periphery. Thecasing I6 fsupports a plurality of freely rotatable pinion the spiral passage 59into a funnel-shaped member 6 I. This member is disposed within thelarger perforated. As the steam passes upwardly through the perforationsany remaining water will be caught and will run to the bottom of thechamber 62 Where it enters the pipe 64 leading to the suction side ofthe pump 56.

The chamber 62 is disposed within a header 65. The steam which passesthrough the perforations in the upper surface 63 of the chamber 62attacca steam in the jackets 61 is thus superheated by the heat in thecombustion chambers 2|;

The steam from the jackets 61 then passes through the openings 68 andinto the nozzleshaped chambers 69 which eject the steam into the turbinepassage against the turbine blades l1, I8. In the arrangementillustrated the fuel jets 26 may be disposed in a circle alternatelywith respect to the nozzle-shaped chambers 69.

From the rear of the turbine passage the steam is exhausted (togetherwith the products of combustion) through the passage 23 into an annulartank l0.

The annular tank 10 is provided with an annular condenser 1I which iscooled by atmospheric air directed through'it by the annular conduit l2having an inlet opening 13 facing forwardly in the direction of ight ofthe aircraft. The tank l is further cooled by atmospheric air enteringthrough the opening 14. The air entering through this opening passesaround the turbine exhaust pipes 23 and nally emerges through the outletopening 15.

The steam and products of combustion ventering the inner annular space16- in the tank 10 must pass through the condenser I I. The waterresulting from condensation of the steam and ,water vapors in theproducts of combustion within the tank 10 and by the condenser 1|,emerges `from the tank I0 at the bottom through an opening 'l1 whichconnects with the return pipe 18 where it is forced by the return pump19 through pipe 80 back to the upper end of the annular4 water tank 55.

The uncondensed products of combustion which pass through the condenser'Il to the upper portion 8l of the annular tank 10 will emerge throughthe opening 82 and will be dissipated tothe atmosphere through theoutlet passage 83.

Any Water which may pass with the uncondensed products of combustionthrough the condenser 1I into the upper part 8l of tank 10 is caught bythe downwardly curved lips 84 sur-,

rounding the opening 82. Such Vwater will eventually makeV its way tothe bottom of the tank 10 where it will pass through opening 'I1 intothe return pipe 13.

The system describe.' thus utilizes the heat Aof the turbine to convertthel cooling water into steam, which ysteam isV directed againstthevturbine blades to assist in driving them. This steam also aids incooling the turbine blades. The steam after performing its useful workis again converted to water and returned to the water reservoir for thevcooling jacket of the turbine. Moreover, and very important in selfpropelled vehicles and particularly in aircraft where Vlightness ofweight is of great importance andY large supplies of water cannotbecarried, the system Are-` covers water formed during combustion andpresent in the products of combustion passing through the turbine andadds such water to that originally in the water reservoir. This makespossible long duration operation of the turbine at high emest4 NumberName 1,139,696 I Maxwell May 18,1915 1,381,872 v VGuerini June 14, 19211,632,157i ,wondra June 14, 1927 1,929,427 Holzwarth Oct. 10, 19331,987,604 Corbett Jan. 15, 1935 2,223,953 Davis Dec. 3, 1940 2,310,767Drr Feb.'V 9, 1943 2,416,389 Heppner- Feb. 25, 1947 FOREIGN PATENTS-Number Country Date A25,199 Great Britain 1 -L Nov. 19, 1904 148,823Great Britain Feb. 9, 1922 459,924 Great Britain Jan. 18, 1937 v545,295Great Britain v.- May. 19, 1942 360,323 Germany Oct. 6, 1922 coming adefect in previous turbines whose waterI supply diminished continuouslyduring operation, and which therefore were incapable of long durationcontinuous operation on a small capacity water supply.

The arrangement shown by way of example is direct, simple and eflicient.Manifestly, the invention may be applied to other types of turbinearrangements, and the invention should not be limited in scope except aslimited in the following claim.

What I claim is:

A turbine for use as a power source in aircraft, comprising a rotatabledrive shaft, a rotatable hollow cylindrical turbine member operablyconnected to said drive shaft, turbine blades extend- -ing radiallyinwardly and outwardly from said member, conduit means for directing airthrough said inwardly extending blades, combustion means utilizing saidair after movement through said inwardly extending blades and arrangedto ,direct products of combustion against said outwardly extendingblades, an annular water tank surrounding said drive shaft, a waterjacket sur' rounding the area dened by the outwardly extendingA turbineblades of said hollow member whereby said area is cooled and the waterin said jacket is converted to steam, means for injecting steam formedduring passage of the water through said jacket against said outwardlyextending turbine blades at the point where said products of combustionbegin passage through .said outwardly extending turbine blades,condensing means receiving-the fluids emerging from passage through saidoutwardly extending blades `for condensing waterfrom said steam andprod- REFERENCES CITE!)V The' following references are of'record in thefile of this patent: 1

UNITED STATES PATENTS l Date

